Corrosion is the destructive attack of a metal by chemical or electrochemical reaction with its environment. In some instances, chemical attack accompanies physical deterioration and results in corrosive wear. Corrosion in electrical or electronic devices is particularly harmful since these types of devices are very susceptible to performance deterioration when any of the electrical components corrode. Corrosion prevention stems from economic, safety, and conservation concerns. With respect to electronic products, economics and safety are the prime factors in motivating corrosion prevention research.
Battery powered electrical devices typically have electrical contacts where a replaceable battery may be connected to the device. Likewise, the battery intended for attachment to and for energizing the electrical equipment necessarily must have battery terminals which are intended to mate with the corresponding terminals of the electrical equipment. These contacts or terminals of the battery and the electrical equipment are exposed when the battery or battery pack is separated from the equipment portion which it powers and also when the battery or battery pack is connected to the electrical equipment. When the battery powered electrical equipment is used in a corrosive environment, such as that experienced near coastlines, electrochemical corrosion of the battery terminals results.
There have been attempts in the past to solve this problem. One of these attempts involves environmentally sealing or isolating the electrical contacts of the battery and the electrical device from the corrosive environment. This provides a solution only while the battery is connected to the electrical device, leaving the problem of corrosion during the time when the battery is removed from the device. Also, any violation of the integrity of the environmental seal will result in corrosion of the battery terminals.
Another attempt to solve this problem has been to use noble metals as the contact surfaces of the battery terminals and the electrical device supply terminals. Plating the contacts with material such as gold, platinum or silver does eliminate corrosion in marine environments, however, this is an expensive solution to the problem and the noble metal plating eventually wears away, thereby exposing the underlying metal to possible corrosion.
What is needed then, is a method of eliminating the corrosion of battery terminals in marine environments that does not require expensive noble metal plating or complicated environmental sealing mechanisms.